Affecting the vast majority of people older than 65, cervical spondylotic myelopathy (CSM) is the leading cause of spinal cord dysfunction in the United States and across the world.
It occurs when vertebrae in the neck, also called the cervical spine, begin to compress the spinal cord, leading to a wide variety of symptoms, including tingling or numbness in the hands and arms, loss of coordination and balance, bladder dysfunction, and pain or stiffness in the neck.
In the United States, more than 100,000 patients with severe symptoms decide to undergo surgery for CSM each year. However, few studies provide evidence as to which of the several surgical approaches available lead to optimal patient outcomes.
In a new study published in JAMA, researchers led by neurosurgeons at Lahey Hospital & Medical Center (LHMC) conducted a randomized clinical trial to compare a ventral surgical approach, in which surgeons access the cervical spine via the front of the neck, to a dorsal surgical approach, in which surgeons access the cervical spine through an incision in the back of the neck, for the treatment of CSM.
The first-of-its kind trial followed 163 patients with CSM treated at 15 medical centers in North America for two years after undergoing one of the procedures. The team found no significant differences between the ventral and dorsal approaches in patients' long-term physical improvements.
Likely the result of our aging population, surgery for treatment of cervical spondylotic myelopathy is on the rise, yet the optimal surgical approach remains unknown and complications are common. As confirmed by this trial, surgery is an effective treatment for myelopathy and both ventral and dorsal surgeries were associated with clinically meaningful improvements in patient-reported physical functioning."
Zoher Ghogawala, MD, Study First Corresponding Author and Chair of Department of Neurosurgery, Lahey Hospital & Medical Center and Professor of Neurosurgery, School of Medicine, Tufts University
Ghogawala and 23 colleagues at 15 sites in the United States and Canada randomized 163 patients ages 45 to 80 to either ventral or dorsal surgery for the treatment of severe CSM. Ultimately, 66 patients underwent ventral surgery, which is often most appropriate for patients with arthritis in the neck and/or a bent forward posture.
The remaining 97 underwent one of two dorsal procedures. To assess how the surgeries affected patients' physical function and quality of life, patients filled out a validated and standardized survey of functional and quality of life outcomes prior to surgery and at three, six, 12 and 24 months after surgery.
The researchers determined that patients' survey scores did not differ significantly between the ventral and dorsal groups. Ventral surgery was associated with more complications when compared with dorsal surgery.
Within the dorsal group, the researchers compared outcomes for dorsal fusion surgery -; a procedure in which bone and disk tissue is removed to relieve the pressure on the cervical spine -; and dorsal laminoplasty, a procedure in which no bone or tissue is removed but rather the spinal canal is expanded -; more commonly performed in Asia and Europe. In this study, in a non-randomized comparison, the scientists found significant association between the type of surgery and patient outcomes.
Specifically, dorsal laminoplasty was associated with significantly greater improvement in patients' self-reported outcomes compared with dorsal fusion. Dorsal laminoplasty was also associated with the lowest risk of complications compared to both dorsal and ventral fusion procedures. Dorsal laminoplasty was also associated with significantly less outpatient health resource utilization and less opioid usage.
"In this trial, laminoplasty was associated with improved outcomes and less outpatient medical service utilization post-operatively than ventral fusion or dorsal fusion surgery," said Ghogawala. "In the United States, charges and Medicare payments for laminoplasty procedures are lower than for fusion procedures. Our study underscores the importance of more extensive and formal economic analysis to examine the societal cost effectiveness of these three alternative surgical approaches."
Ghogawala, Z., et al. (2021) Effect of Ventral vs Dorsal Spinal Surgery on Patient-Reported Physical Functioning in Patients With Cervical Spondylotic Myelopathy. JAMA. doi.org/10.1001/jama.2021.1233.